In Gonghe Basin， hot dry rock resources are enriched in granite strata with high hardness and strong abrasiveness， and well developed cracks over some well sections， which leads to difficult core drilling. According to the characteristics of hot dry rock formation and coring demand， the KT178 coring tool was developed， and the impregnated diamond coring bit was designed. The drilling tool was a swivel type double tube core barrel， which can be used with the down-hole motor. The strength check of key components， such as outer barrel， core catcher， was emphasized in the design. The drilling tools have been improved and established through two rounds of experiments and optimization at Well GH-01 and GH-02 with fairly intact core samples obtained， meeting the requirements for coring in hot dry rock exploration. The drilling tools can be extended to similar projects with intermittent coring requirements， such as exploration of shale gas and water resources.